X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=Documentation%2Fgitattributes.txt;h=cf4ee2ebe5d8a10e23d129a0b8e7788de3f2dcf1;hb=c05ef93879696638406cad5be54be577a2666d04;hp=b6f90f6f37b5ab28096fdc3a7cb3dbc35fa82175;hpb=3fed15f568c24ec00ef78fddc6cbb881fbbb0277;p=git.git diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt index b6f90f6f3..cf4ee2ebe 100644 --- a/Documentation/gitattributes.txt +++ b/Documentation/gitattributes.txt @@ -72,8 +72,8 @@ EFFECTS ------- Certain operations by git can be influenced by assigning -particular attributes to a path. Currently, three operations -are attributes-aware. +particular attributes to a path. Currently, the following +operations are attributes-aware. Checking-out and checking-in ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -138,29 +138,59 @@ upon checkout. ^^^^^^^ When the attribute `ident` is set to a path, git replaces -`$ident$` in the blob object with `$ident:`, followed by +`$Id$` in the blob object with `$Id:`, followed by 40-character hexadecimal blob object name, followed by a dollar sign `$` upon checkout. Any byte sequence that begins with -`$ident:` and ends with `$` in the worktree file is replaced -with `$ident$` upon check-in. +`$Id:` and ends with `$` in the worktree file is replaced +with `$Id$` upon check-in. + + +`filter` +^^^^^^^^ + +A `filter` attribute can be set to a string value that names a +filter driver specified in the configuration. + +A filter driver consists of a `clean` command and a `smudge` +command, either of which can be left unspecified. Upon +checkout, when the `smudge` command is specified, the command is +fed the blob object from its standard input, and its standard +output is used to update the worktree file. Similarly, the +`clean` command is used to convert the contents of worktree file +upon checkin. + +A missing filter driver definition in the config is not an error +but makes the filter a no-op passthru. + +The content filtering is done to massage the content into a +shape that is more convenient for the platform, filesystem, and +the user to use. The key phrase here is "more convenient" and not +"turning something unusable into usable". In other words, the +intent is that if someone unsets the filter driver definition, +or does not have the appropriate filter program, the project +should still be usable. Interaction between checkin/checkout attributes ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ In the check-in codepath, the worktree file is first converted -with `ident` (if specified), and then with `crlf` (again, if -specified and applicable). +with `filter` driver (if specified and corresponding driver +defined), then the result is processed with `ident` (if +specified), and then finally with `crlf` (again, if specified +and applicable). In the check-out codepath, the blob content is first converted -with `crlf`, and then `ident`. +with `crlf`, and then `ident` and fed to `filter`. Generating diff text ~~~~~~~~~~~~~~~~~~~~ The attribute `diff` affects if `git diff` generates textual -patch for the path or just says `Binary files differ`. +patch for the path or just says `Binary files differ`. It also +can affect what line is shown on the hunk header `@@ -k,l +n,m @@` +line. Set:: @@ -185,7 +215,8 @@ String:: Diff is shown using the specified custom diff driver. The driver program is given its input using the same calling convention as used for GIT_EXTERNAL_DIFF - program. + program. This name is also used for custom hunk header + selection. Defining a custom diff driver @@ -210,6 +241,50 @@ parameters, just like `GIT_EXTERNAL_DIFF` program is called. See gitlink:git[7] for details. +Defining a custom hunk-header +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Each group of changes (called "hunk") in the textual diff output +is prefixed with a line of the form: + + @@ -k,l +n,m @@ TEXT + +The text is called 'hunk header', and by default a line that +begins with an alphabet, an underscore or a dollar sign is used, +which matches what GNU `diff -p` output uses. This default +selection however is not suited for some contents, and you can +use customized pattern to make a selection. + +First in .gitattributes, you would assign the `diff` attribute +for paths. + +------------------------ +*.tex diff=tex +------------------------ + +Then, you would define "diff.tex.funcname" configuration to +specify a regular expression that matches a line that you would +want to appear as the hunk header, like this: + +------------------------ +[diff "tex"] + funcname = "^\\(\\\\\\(sub\\)*section{.*\\)$" +------------------------ + +Note. A single level of backslashes are eaten by the +configuration file parser, so you would need to double the +backslashes; the pattern above picks a line that begins with a +backslash, and zero or more occurrences of `sub` followed by +`section` followed by open brace, to the end of line. + +There are a few built-in patterns to make this easier, and `tex` +is one of them, so you do not have to write the above in your +configuration file (you still need to enable this with the +attribute mechanism, via `.gitattributes`). Another built-in +pattern is defined for `java` that defines a pattern suitable +for program text in Java language. + + Performing a three-way merge ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -308,7 +383,7 @@ abc -foo -bar the attributes given to path `t/abc` are computed as follows: 1. By examining `t/.gitattributes` (which is in the same - diretory as the path in question), git finds that the first + directory as the path in question), git finds that the first line matches. `merge` attribute is set. It also finds that the second line matches, and attributes `foo` and `bar` are unset. @@ -319,12 +394,12 @@ the attributes given to path `t/abc` are computed as follows: and `bar` attributes should be given to this path, so it leaves `foo` and `bar` unset. Attribute `baz` is set. -3. Finally it examines `$GIT_DIR/info/gitattributes`. This file +3. Finally it examines `$GIT_DIR/info/attributes`. This file is used to override the in-tree settings. The first line is a match, and `foo` is set, `bar` is reverted to unspecified state, and `baz` is unset. -As the result, the attributes assignement to `t/abc` becomes: +As the result, the attributes assignment to `t/abc` becomes: ---------------------------------------------------------------- foo set to true